AddParens only if it is not already a ParenthesizedExpressionSyntax

Author: LucTremblay

CodeConverter/Util/CSharpUtil.cs

@@ -131,6 +131,8 @@ public static SyntaxKind GetExpressionOperatorTokenKind(SyntaxKind op)
     /// </summary>
     public static ExpressionSyntax AddParens(this ExpressionSyntax expression)
     {
+        if (expression is ParenthesizedExpressionSyntax)
+            return expression;
         return SyntaxFactory.ParenthesizedExpression(expression);
     }